Browsing by Author "Lin, Chung-Kwei"

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Effect of Sn-doped on microstructural and optical properties of ZnO thin films deposited by sol-gel method
(2008-12-01)
Tsay, Chien-Yie
;
Cheng, Hua-Chi
;
Tung, Yen-Ting
;
Tuan, Wei-Hsing
;
Lin, Chung-Kwei
In this study, transparent thin films of Sn-doped ZnO (ZnO:Sn) were deposited onto alkali-free glass substrates by a sol-gel method; the effect of Sri doping on crystallinity, microstructural and optical properties was investigated. The atomic percentages of dopant in ZnO-based sols were Sn/Zn = 0, 1, 2, 3, and 5 at.%. The as-deposited films were pre-heated at 300 degrees C for 10 min and then annealed in air at 500 degrees C for 1 h. The results show that Sn-doped ZnO thin films demonstrate obviously improved surface roughness, enhanced transmittance in the 400-600 nm wavelength range and reduced average crystallite size. Among all of the annealed ZnO-based films in this study, films doped with 2 at.% Sn concentration exhibited the best properties, namely an average transmittance of 90%, an RMS roughness value of 1.92 nm and a resistivity of 9.3 x 10(2) Omega-cm. (C) 2008 Elsevier B.V All rights reserved.
Growth factors-loaded calcium phosphate/polymer hybrid coating with sequential release behavior prepared via electrochemical deposition method
(2016-10-15)
Sar, Jenny I-Chun
;
Lin, Yen-Zhu
;
Lin, Chung-Kwei
;
Liu, Tse-Ying
;
Chen, San-Yuan
In this study, the dicalcium phosphate dehydrate (DCPD)/carboxymethyl hexanoyl chitosan (CHC) hybrid coating layer with sequential release of BMP-2 and TGF-beta 1 was deposited onto Ti6Al4V substrate by electrochemical co-precipitation method. Different concentrations of amphiphatic chitosan derivative (carboxymethyl hexanoyl chitosan, CHC), BMP-2 and TGF-beta 1-loaded PLA microspheres (PLA/TGF-beta 1 MSs) were co-precipitated with the precursor of DCPD. The resulting DCPD/CHC hybrid coating incorporated with BMP-2 and PLA/TGF-beta 1 MSs was designed for improving the osteoconductive and osteoinductive functionalities of Ti6Al4V. FTIR spectroscopy and X-ray diffraction were used to characterize these hybrid coatings. The drug release profile, MC3T3-E1 cell proliferation and alkaline phosphatase activity were used to investigate the functionality of these hybrid coatings. It was found that the incorporation of CHC could be used as a mean to manipulate the release behavior of growth factor from the DCPD/CHC hybrid coating. In addition, the BMP-2- and PLA/TGF-beta 1 MSs-incorporated DCPD/CHC hybrid coating exhibited a sequential release of BMP-2 and TGF-beta 1 during the first and second two weeks, respectively. Importantly, the DCPD/CHC hybrid coating immersed in simulated body fluid gradually transformed to hydroxyapatite phase. Hence, the BMP-2 and PLA/TGF-beta 1 MSs-incorporated DCPD/CHC hybrid coating exhibited the best cell viability and the highest ALP activity after 14 days. The biocompatible hybrid coating with sequential release functionality proposed in the present study can enhance the osseointegration process and possess promising potential for clinical applications in bone implants and tissue engineering. (C) 2016 Elsevier B.V. All rights reserved.
Growth factors-loaded calcium phosphate/polymer hybrid coating with sequential release behavior prepared via electrochemical deposition method
(2016-10-15)
Sar, Jenny I-Chun
;
Lin, Yen-Zhu
;
Lin, Chung-Kwei
;
Liu, Tse-Ying
;
Chen, San-Yuan
In this study, the dicalcium phosphate dehydrate (DCPD)/carboxymethyl hexanoyl chitosan (CHC) hybrid coating layer with sequential release of BMP-2 and TGF-beta 1 was deposited onto Ti6Al4V substrate by electrochemical co-precipitation method. Different concentrations of amphiphatic chitosan derivative (carboxymethyl hexanoyl chitosan, CHC), BMP-2 and TGF-beta 1-loaded PLA microspheres (PLA/TGF-beta 1 MSs) were co-precipitated with the precursor of DCPD. The resulting DCPD/CHC hybrid coating incorporated with BMP-2 and PLA/TGF-beta 1 MSs was designed for improving the osteoconductive and osteoinductive functionalities of Ti6Al4V. FTIR spectroscopy and X-ray diffraction were used to characterize these hybrid coatings. The drug release profile, MC3T3-E1 cell proliferation and alkaline phosphatase activity were used to investigate the functionality of these hybrid coatings. It was found that the incorporation of CHC could be used as a mean to manipulate the release behavior of growth factor from the DCPD/CHC hybrid coating. In addition, the BMP-2- and PLA/TGF-beta 1 MSs-incorporated DCPD/CHC hybrid coating exhibited a sequential release of BMP-2 and TGF-beta 1 during the first and second two weeks, respectively. Importantly, the DCPD/CHC hybrid coating immersed in simulated body fluid gradually transformed to hydroxyapatite phase. Hence, the BMP-2 and PLA/TGF-beta 1 MSs-incorporated DCPD/CHC hybrid coating exhibited the best cell viability and the highest ALP activity after 14 days. The biocompatible hybrid coating with sequential release functionality proposed in the present study can enhance the osseointegration process and possess promising potential for clinical applications in bone implants and tissue engineering. (C) 2016 Elsevier B.V. All rights reserved.
Performance of sol-gel deposited Zn1-xMgxO films used as active channel layer for thin-film transistors
(2007-12-15)
Tsay, Chien-Yie
;
Cheng, Hua-Chi
;
Wang, Min-Chi
;
Lee, Pee-Yew
;
Chen, Chia-Fu
ZnO thin-film transistors (TFTs) have attracted considerable R&D interest due to their high transparency and low photosensitivity compared with typical a-Si:H TFTs. The electrical characteristics of ZnO thin films may be controlled by doping with ternary element, for instance Al, Ga, In, Mg, Zr, etc. In this study, Zn1-x ,MgxO (x= 0 to 0.36) thin films were deposited on glass substrates by spin coating. The as-deposited films were baked at 300 degrees C for 10 min and then annealed at 500 degrees C for I h in air. The results show that, addition of Mg-species in ZnO films markedly enhanced the uniformity of film thickness and improved optical properties. The Zn0.8Mg0.2O film exhibited the best transparency of 92%, an increase of similar to 15% over a pure ZnO film, and the rms roughness value decreased to 1.63. The Zn1-x .,MgxO TFTs were demonstrated to have n-type enhancement behavior. The optimum device with Zn0.8Mg0.2O channel layer had a field-effect mobility of 0.1 cm(2) /V s, a threshold voltage of 6.0 V, and an on/off ratio more than 10(7). (c) 2007 Elsevier B.V. All rights reserved.